Re #1762: Change alloc method for preview layer that may cause crash when releasing the object on iOS 7 (arm64).



git-svn-id: http://svn.pjsip.org/repos/pjproject@4902 74dad513-b988-da41-8d7b-12977e46ad98
Misc (re #1751): Fixed wrong pointer check in starting video render device.



git-svn-id: http://svn.pjsip.org/repos/pjproject@4903 74dad513-b988-da41-8d7b-12977e46ad98
Re #1758: update default OpenH264 video size for iPhone device to 352x288 (on 4S, 720x480 seems to be too heavy for the CPU).



git-svn-id: http://svn.pjsip.org/repos/pjproject@4904 74dad513-b988-da41-8d7b-12977e46ad98
Misc (re #1751): Avoid confusion caused by double variable declaration. (Thanks Itay Bianco for the report).



git-svn-id: http://svn.pjsip.org/repos/pjproject@4905 74dad513-b988-da41-8d7b-12977e46ad98